Watson State Bank of Watson, Minn., became the 168th bank nationwide to fail this year, the Federal Deposit Insurance Corp. said. The board of the FDIC approved assumption of the deposits and other liabilities of Watson State Bank by Minnwest Bank of Montevideo, Minn., a FDIC spokesman said. The failed bank’s sole office will reopen today as a branch of Minnwest, and its depositors will automatically become depositors of the assuming bank. Minnwest bank will assume about $11.8 million in 2,300 deposit accounts and has agreed to pay FDIC a purchase premium of $166,000. It also will purchase about $7.9 million of the failed bank’s assets, including $211,000 of the its small loans.